1. Field of the Invention
Aspects of the present invention relate to a lithium rechargeable battery, and more particularly, to a lithium rechargeable battery having a battery pack with an optimized structure.
2. Description of the Related Art
In general, lithium rechargeable batteries can be classified as a cylindrical battery, a polygonal battery, and a pouch-type battery, in accordance with the shape of a case in which an electrode assembly and an electrolyte are accommodated. In a pouch-type battery, the electrode assembly is accommodated in a pouch, to form a bare cell, and the electrode assembly is connected to a protecting circuit board, to form a battery pack.
In the above-described pouch-type battery, in the electrode assembly, electrode tabs drawn from two electrodes are electrically connected to the protecting circuit board, via a lead plate. The protecting circuit board faces a surface from which the electrode tabs extend from the bare cell.
When the specification of an electrical device varies, or when the size of the protecting circuit board changes, the protecting circuit board can be provided on a surface from which the electrode tabs are not drawn. In such a case, since the electrode tabs are further separated from the protecting circuit board, the length of the lead plate increases. Therefore, the longer lead plate increases internal resistance of the battery.
As described above, in a lithium rechargeable battery, the structure of the lead plate has a large influence on optimizing the structure of the battery pack.